Existing drugs like steroids keep the disease under control by broadly suppressing the immune system but cause nasty side effects.

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's (nyse: PFE - news - people ) Lipitor or Merck 's (nyse: MRK - news - people ) Zocor cut the odds of heart attack or stroke in high-risk patients by a third, but they also can cause side effects that destroy muscle tissue and, eventually, the liver.

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But the drug can have side effects and cause adverse events, including heart failure, in a small minority.

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That drug has not only liver side effects, but also must be injected and can cause painful injection-site reactions.

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But deadly side effects--a swelling of the nose and throat that can cause suffocation--turned up in late-stage clinical trials.

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Emergency contraception is effective for the first 72 hours after sex, but is more likely to work the sooner it is taken, and can cause side-effects such as nausea and diarrhoea in some women.

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The glare might cause your eyes to tire but there is no danger of radiation or other undesirable side-effects.

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But scientists count deaths from any cause to measure drugs, because it prevents fudging of data and takes side effects into account.

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But interferon-ribavirin regimens clear the most common strain only half the time at most and cause an array of nasty side effects.

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